Typical plug and receptacle connectors are mated together by hand. In some instances, however, larger plug and receptacle connectors are mated together with mating tools using leverage or screws.
However, use of such mating tools limits the freedom of designing, and extra space is required for equipping the electric connector with such a mating tool. For example, where a mating tool uses a screw, the screw is fixed to the center of the connector to permit the mating force to be distributed evenly. This arrangement makes it difficult to reduce the size of the connector. Similarly, for a leverage tool, such as a lever or cam, a relatively large space is required to permit rotation of the lever or cam about a fulcrum in the connector.